How do I learn How to Hack? - Hands On Cybersecurity Experience

One of the top questions I hear is "How do I learn how to hack?"
The short answer: by doing.
Here is a list of websites that offer free hacking/programming/cybersecurity challenges that provide real-world experience without having to pay an absurd amount of money or risking any legal troubles.

https://www.enigmagroup.org
http://flaws.cloud/
http://canyouhack.it/
https://www.vulnhub.com/
http://smashthestack.org
https://pentesterlab.com/
https://www.hackthissite.org
https://ctftime.org/
https://ctf365.com/
http://overthewire.org/wargames/
https://www.hellboundhackers.org/
http://io.netgarage.org/
https://microcorruption.com/login
https://pwn0.com/
http://pwnable.kr/
https://w3challs.com/
http://ghostintheshellcode.com/